According to research presented Monday at Sleep 2011, the annual meeting of the Associated Profession Sleep Societies, cooling the brain and can reduce the amount of time it takes people with insomnia to fall asleep -- and increase the length of time they stay that way.

To achieve "frontal cerebral thermal transfer," as the cooling is called, researchers Dr. Eric Nofzinger and Dr. Daniel Buysse of the Sleep Neuroimaging Research Program at the University of Pittsburgh School of Medicine outfitted 24 people -- 12 with insomnia, and 12 without -- with soft plastic caps. The caps had tubes for circulating water at neutral, moderate or maximum "cooling intensity."

The team observed how well participants slept with and without the caps, and at the different temperature levels. Patients with insomnia who were treated at maximum cooling intensity for the whole night took about 13 minutes to fall asleep and slept 89% of the time that they were in bed, the researchers said. That's similar to the sleep enjoyed by healthy study subjects who didn't have insomnia (who took 16 minutes to fall asleep and also slept 89% of the time).

The method is effective because it slows metabolism in the frontal cortex, according to the presenters. Insomnia is associated with increased metabolism in that part of the brain; reduced metabolism, apparently, has the opposite effect.

In a press release, Nofzinger noted that only 25 percent of patients on sleeping pills said they were satisfied with the drugs, which can cause side effects and dependence. The cooling caps may provide an effective, safe and natural alternative. "We believe this has far-reaching implications for how insomnia can be managed in the future," he said.